[apple/xnu.git] / bsd / kern / qsort.c

/*
 * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved
 *
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)qsort.c	8.1 (Berkeley) 6/4/93
 */


#include <sys/types.h>
//#include <stdlib.h>
#include <sys/kpi_private.h>

__private_extern__
void
qsort(void *a, size_t n, size_t es, int (*cmp)(const void *, const void *));

static inline char	*med3(char *, char *, char *, int (*)(const void *, const void *));
static inline void	 swapfunc(char *, char *, int, int);

#define min(a, b)	(a) < (b) ? a : b

/*
 * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
 */
#define swapcode(TYPE, parmi, parmj, n) { 		\
	long i = (n) / sizeof (TYPE); 			\
	TYPE *pi = (TYPE *) (parmi); 			\
	TYPE *pj = (TYPE *) (parmj); 			\
	do { 						\
		TYPE	t = *pi;			\
		*pi++ = *pj;				\
		*pj++ = t;				\
        } while (--i > 0);				\
}

#define SWAPINIT(a, es) swaptype = ((char *)a - (char *)0) % sizeof(long) || \
	es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1;

static inline void
swapfunc(char *a, char *b, int n, int swaptype)
{
	if(swaptype <= 1) 
		swapcode(long, a, b, n)
	else
		swapcode(char, a, b, n)
}

#define swap(a, b)					\
	if (swaptype == 0) {				\
		long t = *(long *)(a);			\
		*(long *)(a) = *(long *)(b);		\
		*(long *)(b) = t;			\
	} else						\
		swapfunc(a, b, es, swaptype)

#define vecswap(a, b, n) 	if ((n) > 0) swapfunc(a, b, n, swaptype)

static inline char *
med3(char *a, char *b, char *c, int (*cmp)(const void *, const void *))
{
	return cmp(a, b) < 0 ?
	       (cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a ))
              :(cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c ));
}

__private_extern__
void
qsort(void *a, size_t n, size_t es, int (*cmp)(const void *, const void *))
{
	char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
	int d, swaptype, swap_cnt;
	int r;

loop:	SWAPINIT(a, es);
	swap_cnt = 0;
	if (n < 7) {
		for (pm = (char *)a + es; pm < (char *) a + n * es; pm += es)
			for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
			     pl -= es)
				swap(pl, pl - es);
		return;
	}
	pm = (char *)a + (n / 2) * es;
	if (n > 7) {
		pl = a;
		pn = (char *)a + (n - 1) * es;
		if (n > 40) {
			d = (n / 8) * es;
			pl = med3(pl, pl + d, pl + 2 * d, cmp);
			pm = med3(pm - d, pm, pm + d, cmp);
			pn = med3(pn - 2 * d, pn - d, pn, cmp);
		}
		pm = med3(pl, pm, pn, cmp);
	}
	swap(a, pm);
	pa = pb = (char *)a + es;

	pc = pd = (char *)a + (n - 1) * es;
	for (;;) {
		while (pb <= pc && (r = cmp(pb, a)) <= 0) {
			if (r == 0) {
				swap_cnt = 1;
				swap(pa, pb);
				pa += es;
			}
			pb += es;
		}
		while (pb <= pc && (r = cmp(pc, a)) >= 0) {
			if (r == 0) {
				swap_cnt = 1;
				swap(pc, pd);
				pd -= es;
			}
			pc -= es;
		}
		if (pb > pc)
			break;
		swap(pb, pc);
		swap_cnt = 1;
		pb += es;
		pc -= es;
	}
	if (swap_cnt == 0) {  /* Switch to insertion sort */
		for (pm = (char *)a + es; pm < (char *) a + n * es; pm += es)
			for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0; 
			     pl -= es)
				swap(pl, pl - es);
		return;
	}

	pn = (char *)a + n * es;
	r = min(pa - (char *)a, pb - pa);
	vecswap(a, pb - r, r);
	r = min((size_t)(pd - pc), pn - pd - es);
	vecswap(pb, pn - r, r);
	if ((size_t)(r = pb - pa) > es)
		qsort(a, r / es, es, cmp);
	if ((size_t)(r = pd - pc) > es) { 
		/* Iterate rather than recurse to save stack space */
		a = pn - r;
		n = r / es;
		goto loop;
	}
/*		qsort(pn - r, r / es, es, cmp);*/
}

/* private KPI */
void 
kx_qsort (void *array, size_t nm, size_t member_size, int (*cmpf)(const void *, const void *)) {
	qsort (array, nm, member_size, cmpf);
}
Commit	Line	Data
1c79356b	1	/*
2d21ac55	2	* Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
5d5c5d0d	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
2d21ac55 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
8f6c56a5	14	*
2d21ac55 A	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
8f6c56a5	25	*
2d21ac55	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/*
	29	* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved
	30	*
	31	* Copyright (c) 1992, 1993
	32	* The Regents of the University of California. All rights reserved.
	33	*
	34	* Redistribution and use in source and binary forms, with or without
	35	* modification, are permitted provided that the following conditions
	36	* are met:
	37	* 1. Redistributions of source code must retain the above copyright
	38	* notice, this list of conditions and the following disclaimer.
	39	* 2. Redistributions in binary form must reproduce the above copyright
	40	* notice, this list of conditions and the following disclaimer in the
	41	* documentation and/or other materials provided with the distribution.
	42	* 3. All advertising materials mentioning features or use of this software
	43	* must display the following acknowledgement:
	44	* This product includes software developed by the University of
	45	* California, Berkeley and its contributors.
	46	* 4. Neither the name of the University nor the names of its contributors
	47	* may be used to endorse or promote products derived from this software
	48	* without specific prior written permission.
	49	*
	50	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	51	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	52	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	53	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	54	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	55	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	56	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	57	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	58	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	59	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	60	* SUCH DAMAGE.
	61	*
	62	* @(#)qsort.c 8.1 (Berkeley) 6/4/93
	63	*/
	64
	65
	66	#include <sys/types.h>
b4c24cb9	67	//#include <stdlib.h>
3e170ce0	68	#include <sys/kpi_private.h>
b0d623f7 A	69
	70	__private_extern__
	71	void
	72	qsort(void a, size_t n, size_t es, int (cmp)(const void , const void ));
1c79356b	73
2d21ac55	74	static inline char med3(char , char , char , int ()(const void , const void *));
91447636	75	static inline void swapfunc(char , char , int, int);
1c79356b A	76
	77	#define min(a, b) (a) < (b) ? a : b
	78
	79	/*
	80	* Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
	81	*/
	82	#define swapcode(TYPE, parmi, parmj, n) { \
	83	long i = (n) / sizeof (TYPE); \
2d21ac55 A	84	TYPE pi = (TYPE ) (parmi); \
2d21ac55 A	85	TYPE pj = (TYPE ) (parmj); \
1c79356b	86	do { \
2d21ac55	87	TYPE t = *pi; \
1c79356b A	88	pi++ = pj; \
	89	*pj++ = t; \
	90	} while (--i > 0); \
	91	}
	92
	93	#define SWAPINIT(a, es) swaptype = ((char )a - (char )0) % sizeof(long) \|\| \
	94	es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1;
	95
	96	static inline void
2d21ac55	97	swapfunc(char a, char b, int n, int swaptype)
1c79356b A	98	{
	99	if(swaptype <= 1)
	100	swapcode(long, a, b, n)
	101	else
	102	swapcode(char, a, b, n)
	103	}
	104
	105	#define swap(a, b) \
	106	if (swaptype == 0) { \
	107	long t = (long )(a); \
	108	(long )(a) = (long )(b); \
	109	(long )(b) = t; \
	110	} else \
	111	swapfunc(a, b, es, swaptype)
	112
	113	#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype)
	114
	115	static inline char *
2d21ac55	116	med3(char a, char b, char c, int (cmp)(const void , const void ))
1c79356b A	117	{
	118	return cmp(a, b) < 0 ?
	119	(cmp(b, c) < 0 ? b : (cmp(a, c) < 0 ? c : a ))
	120	:(cmp(b, c) > 0 ? b : (cmp(a, c) < 0 ? a : c ));
	121	}
	122
b4c24cb9	123	__private_extern__
1c79356b	124	void
2d21ac55	125	qsort(void a, size_t n, size_t es, int (cmp)(const void , const void ))
1c79356b A	126	{
1c79356b A	127	char pa, pb, pc, pd, pl, pm, *pn;
2d21ac55 A	128	int d, swaptype, swap_cnt;
2d21ac55 A	129	int r;
1c79356b A	130
	131	loop: SWAPINIT(a, es);
	132	swap_cnt = 0;
	133	if (n < 7) {
55e303ae	134	for (pm = (char )a + es; pm < (char ) a + n * es; pm += es)
1c79356b A	135	for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
	136	pl -= es)
	137	swap(pl, pl - es);
	138	return;
	139	}
55e303ae	140	pm = (char )a + (n / 2) es;
1c79356b A	141	if (n > 7) {
1c79356b A	142	pl = a;
55e303ae	143	pn = (char )a + (n - 1) es;
1c79356b A	144	if (n > 40) {
	145	d = (n / 8) * es;
	146	pl = med3(pl, pl + d, pl + 2 * d, cmp);
	147	pm = med3(pm - d, pm, pm + d, cmp);
	148	pn = med3(pn - 2 * d, pn - d, pn, cmp);
	149	}
	150	pm = med3(pl, pm, pn, cmp);
	151	}
	152	swap(a, pm);
55e303ae	153	pa = pb = (char *)a + es;
1c79356b	154
55e303ae	155	pc = pd = (char )a + (n - 1) es;
1c79356b A	156	for (;;) {
	157	while (pb <= pc && (r = cmp(pb, a)) <= 0) {
	158	if (r == 0) {
	159	swap_cnt = 1;
	160	swap(pa, pb);
	161	pa += es;
	162	}
	163	pb += es;
	164	}
	165	while (pb <= pc && (r = cmp(pc, a)) >= 0) {
	166	if (r == 0) {
	167	swap_cnt = 1;
	168	swap(pc, pd);
	169	pd -= es;
	170	}
	171	pc -= es;
	172	}
	173	if (pb > pc)
	174	break;
	175	swap(pb, pc);
	176	swap_cnt = 1;
	177	pb += es;
	178	pc -= es;
	179	}
	180	if (swap_cnt == 0) { /* Switch to insertion sort */
55e303ae	181	for (pm = (char )a + es; pm < (char ) a + n * es; pm += es)
1c79356b A	182	for (pl = pm; pl > (char *) a && cmp(pl - es, pl) > 0;
	183	pl -= es)
	184	swap(pl, pl - es);
	185	return;
	186	}
	187
55e303ae	188	pn = (char )a + n es;
1c79356b A	189	r = min(pa - (char *)a, pb - pa);
1c79356b A	190	vecswap(a, pb - r, r);
2d21ac55	191	r = min((size_t)(pd - pc), pn - pd - es);
1c79356b	192	vecswap(pb, pn - r, r);
2d21ac55	193	if ((size_t)(r = pb - pa) > es)
1c79356b	194	qsort(a, r / es, es, cmp);
2d21ac55	195	if ((size_t)(r = pd - pc) > es) {
1c79356b A	196	/* Iterate rather than recurse to save stack space */
	197	a = pn - r;
	198	n = r / es;
	199	goto loop;
	200	}
	201	/* qsort(pn - r, r / es, es, cmp);*/
	202	}
3e170ce0 A	203
	204	/* private KPI */
	205	void
	206	kx_qsort (void array, size_t nm, size_t member_size, int (cmpf)(const void , const void )) {
	207	qsort (array, nm, member_size, cmpf);
	208	}